Trauma is the most common cause of death in young people, and head injury accounts for almost half of these trauma-related deaths. Head injury severity ranges from concussion to severe traumatic brain injury (TBI). Concussion is broadly defined as an alteration in mental status caused by trauma with or without loss of consciousness. The term concussion is often used synonymously with mild TBI. Grades of TBI are traditionally defined by the Glasgow Coma Scale (GCS) measured 30 minutes after injury (Table 24–7).
Table 24–7.Glasgow Coma Scale.1 |Favorite Table|Download (.pdf) Table 24–7. Glasgow Coma Scale.1
|Points ||Eye Opening ||Verbal Response ||Motor Response |
|1 ||None ||None ||None |
|2 ||To pain ||Vocal but not verbal ||Extension |
|3 ||To voice ||Verbal but not conversational ||Flexion |
|4 ||Spontaneous ||Conversational but disoriented ||Withdraws from pain |
|5 ||Spontaneous ||Oriented ||Localizes pain |
|6 ||Spontaneous ||Oriented ||Obeys commands |
Head trauma may cause cerebral injury through a variety of mechanisms (Table 24–8). Central to management is determination of which patients need head imaging and observation. Of particular concern is identification of patients with epidural and subdural hematoma, who may present with normal neurologic findings shortly after injury (lucid interval) but rapidly deteriorate thereafter, and in whom surgical intervention is life-saving.
Table 24–8.Acute cerebral sequelae of head injury. |Favorite Table|Download (.pdf) Table 24–8. Acute cerebral sequelae of head injury.
|Sequelae ||Clinical Features ||Pathology |
|Concussion ||A transient, trauma-induced alteration in mental status that may or may not involve loss of consciousness. Symptoms and signs include headache, nausea, disorientation, irritability, amnesia, clumsiness, visual disturbances, and focal neurologic deficit. || |
Unknown; likely mild diffuse axonal injury and excitotoxic neuronal injury.
Cerebral contusion may occur.
|Cerebral contusion or laceration ||Loss of consciousness longer than with concussion. Focal neurologic deficits are often present. May lead to death or severe residual neurologic deficit. || |
Bruising on side of impact (coup injury) or contralaterally (contrecoup injury).
Vasogenic edema, multiple petechial hemorrhages, and mass effect. May have subarachnoid bleeding. Herniation may occur in severe cases. Cerebral laceration specifically involves tearing of the cerebral tissue and pia-arachnoid overlying a contusion.
|Acute epidural hemorrhage ||Headache, confusion, somnolence, seizures, and focal deficits occur several hours after injury (lucid interval) and lead to coma, respiratory depression, and death unless treated by surgical evacuation. ||Tear in meningeal artery, vein, or dural sinus, leading to hematoma visible on CT scan. |
|Acute subdural hemorrhage ||Similar to epidural hemorrhage, but interval before onset of symptoms is longer. Neurosurgical consultation for consideration of evacuation. ||Hematoma from tear in veins ...|